The present invention relates to zeolite UZM-43, the process of making it and its use as a catalyst in hydrocarbon conversion processes. This zeolite is represented by the empirical formula:Mm+R1r1R2r2Al1-xExSiyOz where M represents sodium or a combination of sodium and potassium exchangeable cations, “m” is the mole ratio of M to (Al+E) and varies from about 0.05 to about 5, R1 is a singly charged propyltrimethylammonium cation, “r1” is the mole ratio of R to (Al+E) and has a value of about 0.25 to about 8.0, R2 is an amine, “r2” is the mole ratio of R to (Al+E) and has a value of about 0.0 to about 5, E is an element selected from the group consisting of gallium, iron, boron and mixtures thereof, “x” is the mole fraction of E and has a value from 0 to about 1.0, “y” is the mole ratio of Si to (Al+E) and varies from greater than 5 to about 40 and “z” is the mole ratio of 0 to (Al+E) and has a value determined by the equation: z=(m+r1+r2+3+4·y)/2. The zeolite UZM-43 has an intergrowth of framework EUO-NES-NON. It may be present in the catalyst as unmodified zeolite UZM-43 or as UZM-43 modified zeolite. The UZM-43 containing catalyst may take one of several forms, including for example, a spherical oil-dropped catalyst or an extruded catalyst.
Zeolites are crystalline aluminosilicate compositions which are microporous and which are formed from corner sharing AlO2 and SiO2 tetrahedra. Numerous zeolites, both naturally occurring and synthetically prepared, are used in various industrial processes. Synthetic zeolites are prepared via hydrothermal synthesis employing suitable sources of Si, Al and structure directing agents such as alkali metals, alkaline earth metals, amines, or organoammonium cations. The structure directing agents reside in the pores of the zeolite and are largely responsible for the particular structure that is ultimately formed. These species balance the framework charge associated with aluminum and can also serve as space fillers. Zeolites are characterized by having pore openings of uniform dimensions, having a significant ion exchange capacity, and being capable of reversibly desorbing an adsorbed phase which is dispersed throughout the internal voids of the crystal without significantly displacing any atoms which make up the permanent zeolite crystal structure. Zeolites can be used as catalysts for hydrocarbon conversion reactions, which can take place on outside surfaces as well as on internal surfaces within the pore.
The three structure types EUO, NON and NES are closely related and can be constructed from the same two layer building units, LBU A and LBU B, shown below extending in the a′ and b′ axis directions. LBU A consists of TO4-tetrahedra connected in two dimensions to generate a silicate sheet with 12-ring openings. LBU B consists of linear chains of TO4-tetrahedra. To generate the 3-dimensional framework structures for EUO, NON and NES, the two layer types are stacked in characteristic sequences in the c′ axis direction.
Diagrams above show the layer-like building units of the EUO-NES-NON family as seen normal to (0 0 1). (a) Layer A consists of [TO4]-tetrahedra interconnected to form 12-rings and (b) layer B consists of rods of [TO4]-tetrahedra running parallel to a′
The above diagrams show representations of the framework structures and stacking sequences for (a) NON, (b) EUO and (c) NES as seen normal to (1 0 0).
For NON, only LBU A layers are stacked a). The stacking sequence is AA′AA′ where every other A layer is shifted by ½a′ and is designated as A′. Although the individual layers contain 12-rings, the alternating shift of ½a′ blocks access and the resulting NON framework is a dense phase. It is not really a zeolite, but a clathrasil, since it contains cages (designated nns by J. V. Smith1) accessible by pores no larger than 6-rings.
The EUO framework type can be formed b) by inserting a B layer between AA′ double layers giving a stacking sequence AA′BAA′B The resulting framework contains one-dimensional 10-ring channels with side pockets into truncated nns cages.
The NES framework type can be formed c) by alternating A and B layers to give a stacking sequence AB′A′BAB′A′B where A′ and B′ are shifted by ½a′. The resulting framework contains 2-dimensional 10-ring channels normal to the b′ axis.
Several related molecular sieves have been disclosed but there are significant differences between those molecular sieves and those of the present invention. In U.S. Pat. No. 6,123,914 is disclosed an EU-1 and intergrowths of EUO-NES type of molecular sieve that is used to remove amorphous B and aluminum from the channels by using a mild treatment with sodium hydroxide. The present invention involves a silica/alumina material that does not contain boron.
U.S. Pat. No. 7,459,073 discloses a molecular sieve SSZ-47B that is made using templates that have rings and are rigid (N-cyclopentyl-1,4-diaabicyclo[2.2.2]octane cation) that would be more expensive to produce and would produce a zeolite with more EUO character than other materials.
U.S. Pat. No. 5,910,299 discloses a ERS-10 zeolite that is made using a template like 6-azonia spiro-[5,5]-undecane hydroxide. It is claimed to have a Si/Al2 ratio from 50 to pure silica. The present invention is made at lower Si/Al2 ratios than ERS-10.
A new material has been made comprising of an EUO-NES-NON framework intergrowth that has application in hydrocarbon processes.